Glossary · Diligence
Due diligence
Definition
Due diligence is the investigation a buyer, investor or lender carries out before a deal is signed. It tests what the seller has said against the documents: accounts, contracts, permits, people, IT and legal claims. In most deals it runs through a virtual data room, with questions handled in a Q&A log.
Diligence usually splits into workstreams, each with its own advisers: financial, legal, commercial, tax and operational. What they find feeds into the price, into the warranties in the purchase agreement, and sometimes into the decision to walk away.
Where due diligence comes up
On this site, in our guides and in the conversations we've written up.
Guide What is a virtual data room? Mergers and acquisitions are the classic use case: a seller opens a room, invites buyers and their advisers, and runs due diligence through it. Guide The due diligence data room checklist Good providers offer ready-made due diligence templates and AI indexing that auto-classify documents, use them. Guide iDeals VDR review: easy to use, secure and quick to set up Beyond the basics, iDeals has features designed for due diligence. Guide Intralinks VDR review: the security veteran, with a learning curve The platform has an integrated Q&A workflow, so buyers and sellers manage their questions securely in the data room rather than over email chains, and AI-assisted tools help with redaction and parts of the due diligence process. Guide Drooms VDR review: European data sovereignty, with a few caveats It positions itself as a secure, AI-powered platform that makes due diligence faster and easier. Guide Ansarada VDR review: the whole deal in one place, if you need it all The Australian founded provider positions itself as more than a traditional VDR: it manages the entire process from preparation and due diligence through to completion, with AI helping your team. Use case Best virtual data room for M&A A sale or acquisition lives or dies on how cleanly you can share confidential information, run buyer due diligence, and keep control of the process. Use case Best virtual data room for due diligence Due diligence is where deals are won or lost. Use case Best virtual data room for real estate A long-standing specialist in real estate due diligence, strong across DACH, with structured indexing and an in-house AI model. Podcast · Dealcast: The M&A Podcast Intralinks' Deal Flow Predictor: forecasting M&A from the due diligence pipeline SS&C Intralinks co-head Bob Petrocchi explains the company's Deal Flow Predictor on the DealCast podcast: a six-month forward view of global M&A built from the 20,000+ pre-announced deals that pass through Intralinks' due diligence… Podcast · BizNexus Roundup Due diligence 101: a VDR overview with Estelle Black An adviser's view of the data room's role in due diligence. 
Podcast · New Business Radio Let's Talk Business #573: a smart, secure platform for decision-makers (New Business Radio) They explain how listed, private, and state-owned companies use Admincontrol to digitise and secure board work and due diligence, and how the platform serves decision-makers across sectors. 
Podcast · Real Estate Notes Show: Note Investing | Seller Financing Due diligence with AI, ML and data extraction Alex Goldovsky of ProTitle USA on using AI, machine learning and data extraction to speed up due diligence for real estate and note investing. 
Podcast · CLOSE THE DEAL - M&A & Private Equity Podcast Artificial intelligence in the M&A process, with Heiko Engel of SS&C Intralinks A German-language conversation with Heiko Engel of SS&C Intralinks on the promise of AI in M&A: self-assembling data rooms and more automated due diligence, and how close that future really is. 
Podcast · The Dealist The role of virtual data rooms and AI in due diligence The Dealist explores how virtual data rooms and AI are reshaping due diligence in M&A, from secure document exchange to AI-assisted review. 
Podcast · CLOSE THE DEAL - M&A & Private Equity Podcast AI and data rooms: an update with Heiko Engel of SS&C Intralinks In a German-language episode, Heiko Engel of SS&C Intralinks discusses how AI is changing the way teams handle data in M&A, and what AI-based tools mean for due diligence inside the virtual data room. 
Podcast · Estate FM Expo Real 2025: Alexandre Grellier on 22 years of digitising due diligence A short commentary from Drooms co-founder Alexandre Grellier at Expo Real, on how the company has spent more than 20 years professionalising and digitising the due diligence process, especially in real estate.
Podcast · New Business Radio Let's Talk Business #573: a smart, secure platform for decision-makers (New Business Radio) They explain how listed, private, and state-owned companies use Admincontrol to digitise and secure board work and due diligence, and how the platform serves decision-makers across sectors. Podcast · Real Estate Notes Show: Note Investing | Seller Financing Due diligence with AI, ML and data extraction Alex Goldovsky of ProTitle USA on using AI, machine learning and data extraction to speed up due diligence for real estate and note investing. Podcast · CLOSE THE DEAL - M&A & Private Equity Podcast Artificial intelligence in the M&A process, with Heiko Engel of SS&C Intralinks A German-language conversation with Heiko Engel of SS&C Intralinks on the promise of AI in M&A: self-assembling data rooms and more automated due diligence, and how close that future really is. Podcast · The Dealist The role of virtual data rooms and AI in due diligence The Dealist explores how virtual data rooms and AI are reshaping due diligence in M&A, from secure document exchange to AI-assisted review. Podcast · CLOSE THE DEAL - M&A & Private Equity Podcast AI and data rooms: an update with Heiko Engel of SS&C Intralinks In a German-language episode, Heiko Engel of SS&C Intralinks discusses how AI is changing the way teams handle data in M&A, and what AI-based tools mean for due diligence inside the virtual data room. Podcast · Estate FM Expo Real 2025: Alexandre Grellier on 22 years of digitising due diligence A short commentary from Drooms co-founder Alexandre Grellier at Expo Real, on how the company has spent more than 20 years professionalising and digitising the due diligence process, especially in real estate. Related terms
Financial due diligence Diligence on the numbers: earnings, working capital, debt and cash flow behind the headline figures. Legal due diligence The lawyers' review of a company: ownership, key contracts, disputes, licences, employment terms and intellectual property. Vendor due diligence Due diligence a seller commissions on its own business before a sale, so bidders get one independent report up front. Red flag report A short diligence report that lists only the serious issues, instead of describing everything that was reviewed. Q&A module The part of a data room where buyers ask questions and the seller's team answers them, with a full record. Commercial due diligence A test of the target's market, customers, competitors and growth plan, to see whether the business case holds. Operational due diligence Diligence on how the business actually runs: processes, systems, supply chain, sites and people. Tax due diligence A review of the target's tax filings, structures and exposures, so hidden tax liabilities are priced in or covered.